Was thinking about whether Human's could, theoretically, survive on Earth if the sun disappeared. I understand that the Earth would likely freeze over, and so I think I have it down to two potential methods.

2) Underwater cities, which take advantage of the oceans freezing over and the insulation that the ice would to the water beneath.

As far as answers go, I'm looking for opinion, with evidence to back it up. Which would be more plausible? Pros and Cons of each method? Alternate methods?

As an addendum to any who might be pedantic- I know that the sun couldn't simply vanish, and that even if it did, the results might not be apparent for years afterwards. This is a hypothetical arguement, and as such we can assume that the sun does suddenly cease to exist, and that humans have had an opportunity to prepare for that eventuallity.

I once computed that my oil furnace, powered by a gasoline-powered generator (to run the oil pump and electrical circuitry) would run non-stop for nine days on a full 275-gal tank of heating oil.

I also figured that, in order to provide gaseous air to run the furnace, the heat escaping from the house/chimney would vaporize the surrounding atmosphere that might have turned into a liquid/solid and precipitated. (If my rough calculations are right, the precipitated atmosphere on a cooled planet Earth would form a layer about 3¼ inches deep.)

This is without considering that radiation/heat rises up through the earth from the core that might keep the atmosphere gaseous.

Grief is the price we pay for love. (CM Parkes) Our postillion has been struck by lightning. (Unknown) War is always the choice of the chosen who will not have to fight. (Bono) The years tell much what the days never knew. (RW Emerson) Reality is not always probable, or likely. (JL Borges)

As far as answers go, I'm looking for opinion, with evidence to back it up. Which would be more plausible?.

Neither; they would not maintain humanity much longer than (say) surface dwellings could. You would have to design a complete ecosystem with power to grow (or synthesize) food, closed loop recycling of everything (including atmosphere) and pressurization to maintain the right internal pressure. Once you have all that, your problem will be getting _rid_ of the waste heat, not trying to warm it up further.

In terms of where it could go - anywhere. On the surface, under water, underground etc. I'd think the surface would be the easiest.

Was thinking about whether Human's could, theoretically, survive on Earth if the sun disappeared. I understand that the Earth would likely freeze over, and so I think I have it down to two potential methods.

2) Underwater cities, which take advantage of the oceans freezing over and the insulation that the ice would to the water beneath.

As far as answers go, I'm looking for opinion, with evidence to back it up. Which would be more plausible? Pros and Cons of each method? Alternate methods?

As an addendum to any who might be pedantic- I know that the sun couldn't simply vanish, and that even if it did, the results might not be apparent for years afterwards. This is a hypothetical arguement, and as such we can assume that the sun does suddenly cease to exist, and that humans have had an opportunity to prepare for that eventuallity.

If tidal acceleration of the Moon keeps on going the day length will get progressively long and it could be like longer periods without the Sun
Imagine if the Earth started taking 168 hours (7 of our current day lengths) to spin on its axis. The night would be 3.5 times as long as it currently is. The nights would get long and cold.

there's one thing you clearly haven't thought about : if the sun really did vanish - as in not just dying but totally disappearing - what would keep the planets in their orbits ? + orbits around what exactly ?

"Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)

there's one thing you clearly haven't thought about : if the sun really did vanish - as in not just dying but totally disappearing - what would keep the planets in their orbits ? + orbits around what exactly ?

Nothing; they would start to drift apart, since their orbital velocities greatly exceed the velocities needed to escape the remaining net gravitation of the solar system. You might get chance captures, say of asteroids that end up straying near Jupiter. Since the Sun was gone it wouldn't matter much.

I have read a scifi story based around earth being captured gravitationally by a "dark Star" and pulled away from the Sun. The story centered around a scientist who tried to save his family in a home made warm room heated by a coal fire and having to periodicly venture out in a homemade space suit with a pickel jar helmet to gather buckets of frozen air. They were eventually rescued by the professionals who had a nuclear generator to power a sheltered community. I remember thinking that the writer was underestimating the earthquake havoak that being pulled away from the Sun would cause.

Yes. Like pzkpfw says, we would know eight minutes later, not years later. I am reassured that you don't actually suppose the sun could die or disappear all that suddenly. It indicates you're not insane.

So with your underground or underwater cities you are assuming we had time to prepare. Granted, but what you are neglecting to consider is that we would be orbiting nothing. Earth would be a rogue planet free to be flung beyond the Solar system. Perhaps it might be captured by Jupiter or Saturn and become a moon, but who can say? Perhaps it might collide with one of the system's gas giants. Let's not forget all eight planets and sweet little old Pluto wold be going rogue too.

I would go with the underground cities, because how do we know the oceans will not just be lost what with the lack of gravity or planetary rotation? How could the planners for this disaster know for sure?

Utilizing residual geothermal heat is a good idea, and probably the only real option. Obviously it will be hard going. We'd have to power lamps so that crops could photosynthesize. There'd be no question of wasting food and water on cattle or even chickens perhaps unless it was only for the eggs. We'd have to eat tofu and beans. All in all a pretty grim existence. Have you ever smelt a tofu factory? It stinks to high heaven - but, of course, there would be no more high heaven, so it would just stink and the stench would linger among the houses, even worse than the smell from all those beans we'd eaten.

In short: KMN. Kill me now!

And what does the Lord require of you but to love justice, to be merciful and to walk humbly with Him?

I would go with the underground cities, because how do we know the oceans will not just be lost what with the lack of gravity or planetary rotation? How could the planners for this disaster know for sure?

Why do you think that the disappearance of the sun would produce a lack of gravity or planetary rotation ? (Helpful hint: they wouldn't)